Brazilian President Fernando Henrique Cardoso called the floods a national calamity.

After an aerial survey of the flood-affected regions, he said emergency funds would be released as soon as they had assessed the damage.

A total of 46 cities and towns in the two states have been put under the state of emergency.

Troops have moved into these areas to clear roads and dig away the mountains of mud that have covered many neighbourhoods.

They also plan to provide helicopters to evacuate flood victims to hospitals and shelters.

Shelter

"We're in a truly critical state," an Alagoas government spokeswoman told Reuters news agency. "Thousands of people are seeking shelter in schools and gyms and anywhere else that we can find. There's no electricity and little food in many towns."

In Pernambuco too, people are seeking shelter in "any public building that is dry".

Thousands of people are seeking shelter in schools and gyms and anywhere else that we can find

A government official

"Roads, highways and bridges have been washed away and the only way to rescue countless others who are isolated is by boat or helicopters," a civil defence official in Pernambuco's capital Recife told AP news agency.

Television images showed entire towns partially submerged in water and residents moving around the streets in boats.

The rains have caused over a dozen mudslides so far.

Most of the victims were buried under the mud that ploughed through homes perched precariously on the hills.

The rains subsided on Wednesday, but meteorologists say more downpours could be expected.

Coastal regions in the north-east often experience floods during the rainy season that lasts from April to August, but the rains this year have been particularly devastating.